Conventional pressure regulators for automotive fuel systems are typically not positioned directly adjacent the engine manifold. Rather, such pressure regulators are disposed at remote locations and coupled to the engine manifold by a specifically designed conduit, conventionally a flexible hose. Also, the pressure regulator is typically mounted with specific mounting hardware which, together with the necessary conduit, increase the cost of the fuel system. Further, the additional elements required for remote mounting of the pressure regulator and routing the conduit to the engine manifold occupy usable space in the engine compartment.
In many conventional fuel systems, the regulator is mounted internally within the fuel tank. Internal fuel tank mounting positions for pressure regulators have their own difficulties in mounting, servicing and replacement. In certain return-type fuel systems, a pressure regulator is typically secured to or forms a part of a fuel rail whereby the fuel pressure in the fuel rail is regulated and excess fuel is returned to the fuel supply. In such system, the pressure regulator is normally closed and acts essentially as a pressure relief valve which opens at a predetermined pressure to enable excess fuel in the relief rail to return to the fuel supply. In another conventional returnless fuel system, the pressure regulator is similarly attached to or forms part of the fuel rail. However, the pressure regulator acts as a demand-type valve supplying fuel at a regulated pressure to the fuel rail in response to fuel demand. That is, the pressure regulator valve is normally open and regulates the flow of fuel to the fuel rail. In the event of an over-pressure condition, the pressure regulator closes the valve and an over-pressure relief valve typically in the fuel tank opens to relieve system fuel pressure. In both the return and returnless-type fuel systems, it is desirable to provide a vacuum reference on the pressure regulator to the engine intake manifold. However, as noted previously, the vacuum reference is typically coupled between the engine intake manifold and pressure regulator by a flexible hose or conduit. Accordingly, there has developed a need for mounting the pressure regulator for an automotive fuel system in a manner which is less costly and which increases available engine space by eliminating regulator mounting and connecting parts.